The desperate search for a rugby fan missing since Saturday night continued on Tuesday, as officers warned the situation was looking "graver and graver".

South Wales Police have appealed for information from anyone who spotted Ben Thompson in a "distinctive" striped shirt after Wales' Six Nations opener against Ireland in Cardiff.

More than 50 officers have been working on the search for the 34-year-old from Haverfordwest, who had been to the match at the Millennium Stadium.

Specialist search teams, police dogs, and the force helicopter have all also been involved in the hunt to find Mr Thompson. Meanwhile, extensive efforts have been made on social media such as Twitter and Facebook to appeal for any witnesses who may have seen him leaving the city centre.

Chief Inspector Eddie Ough, who is leading the investigation, said the force was focusing its efforts in the Canton area where Mr Thompson was seen on CCTV around 7.07pm near the junction of Leckwith Road and Wellington Street.

He said: “We have a confirmed sighting of Ben on the junction of Wellington Street and Leckwith Road and then we have another sighting of a man who fits the description of Ben on Lawrenny Avenue 10 minutes later.

“On the basis that the first sighting is confirmed, the second by time, date and description is very likely to be Ben and so we are concentrating our efforts in the Lawrenny Avenue area.”

He added: “We have got in excess of 50 officers working on the investigation, including specialist search teams, dogs and the helicopter.

“We’ve had a couple of calls from members of the public following the appeal but we need more. I would urge everyone to please look in their gardens, in any outbuildings such as greenhouses, sheds and garages because Ben may have been injured and sought shelter. We haven’t got anything to suggest any criminality. It looks as though Ben has gone out socialising before being separated from his friends. He is then see on CCTV in an intoxicated state walking towards the west of Cardiff.

“We are hoping someone will look at the picture of Ben in what is a distinctive shirt and remember seeing him on what was a cold night.

“As time goes on, the situation gets graver and graver, however we are still actively looking for Ben for the sake of his worried family.”

On Monday, Mr Thompson's wife Joanne made a heartfelt appeal for anyone who may have seen her husband to call the police.

Mr Thompson is around 5ft 9in, has short black/brown hair, blue eyes and was last seen wearing a white shirt with thin blue stripes, blue jeans and brown boots.

Mrs Thompson, 38, said her husband, a process operator at Pembrokeshire gas plant South Hook LNG, had been in the city centre prior to the game, to which he had won tickets.

The last time she spoke to him was moments after the final whistle when he phoned to tell her he was heading to their favourite Cardiff pub.

“He went up on Friday and got picked up from the Cardiff Airport Travelodge by his colleague Andrew Davies,” she said.

“They then went in to Cardiff city centre before going to the match. I know he came out after the game finished because he phoned me to say he was going to our favourite pub, 10 Feet Tall.

“He stayed there for approximately two hours and left with some of his colleagues who were catching the train back to Haverfordwest.

“Ben stayed with Andrew, who is based in Barry, and they were seen queuing to get in to Mocha Lounge but Andrew had to leave at 6.30pm because his children were ill, leaving Ben on his own.

“Andrew left thinking Ben was going to go into Mocha Lounge but CCTV shows that he didn’t. Instead he is seen walking in the direction of Penarth.

“He was sighted on a road leading towards Penarth and there’s a fuzzy CCTV image of him at around 7pm but that’s the last time we have seen him.”

She added: “Ben was fun, he was athletic, he was 5ft 9in, he had blue eyes and short cropped black/brown hair. He was wearing a white shirt with a thin blue stripe which I know he would’ve rolled up to his elbows. He was also wearing blue jeans and brown boots.

“The police have told me they’re treating it as a priority and they’ve assigned more officers and brought in dogs to help.”

Anyone with information about where Mr Thompson could be should contact police on 029 2033 8465.

WalesOnline is part of Media Wales, publisher of the Western Mail, South Wales Echo, Wales on Sunday and the seven Celtic weekly titles, offering you unique access to our audience across Wales online and in print.